The Bernoulli principal has a very interesting relationship with how a vortex behaves. The Bernoulli principal states in part: "for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy". What this is saying is that when fluid in a pipe encounters a restriction, such as a narrowing of the pipe, the flow will increase in velocity. Along with this increase in velocity, there will be a decrease in pressure, which maintains a constant state of kinetic energy.




The venturi in a carburetor is a good example of this. As the flow of air is drawn through the throat of a carburetor, a narrowing of the diameter of the throat causes an increase in the velocity of the air with a corresponding decrease in air pressure. This low pressure is used to suck fuel out of the float bowl to be mixed with the passing air via carefully measured orifices called jets.




Another manifestation of the Bernoulli principal is found in the lift that an airfoil generates: "The relative air flow parallel to the top surface of an aircraft wing or helicopter rotor blade is faster than along the bottom surface. Bernoulli's principle states that the pressure on the surfaces of the wing or rotor blade will be lower above than below, and this pressure difference results in an upwards lift force. If the relative air flows across the top and bottom surfaces of a wing or rotor are known, then lift forces can be calculated (to a good approximation) using Bernoulli's equations — established by Bernoulli over a century before the first man-made wings were used for the purpose of flight. Note that Bernoulli's principle does not explain why the air flows faster past the top of the wing and slower past the under-side. To understand why, it is helpful to understand circulation, the Kutta condition and the Kutta–Joukowski theorem."




So, what does this have to do with a vortex? Well, a vortex exhibits many of these same traits. Within a fast moving vortex, such as in a Hilsch vortex tube, stratification occurs coaxially throughout the rotating air. If viewed on end, these layers would resemble the rings in a tree trunk.
Each of these layers is rotating at a different velocity, which is the key point. The outermost layer is rotating at the slowest rate. Each subsequent layer towards the center axis is rotating at a faster rate. This means that, according to Bernoulli, there is a negative pressure differential between each layer moving towards the center. The faster the air rotates, the more pressure is decreased. The vortex is essentially creating a vacuum in the middle.
The interesting part is that in order to create a vacuum, compression of the volume of air within the center of a vortex must occur. The vortex is a compressor! Further evidence of compression can be found in the Hilsch tube. A fundamental attribute of compression is the release of heat energy. Refrigerators and air conditioners work on this principal. A hilsch tube creates two flows of air, one hot and one cold. The cold one comes from the center of the vortex, where compression has taken place. As the air exits from the tube, it expands from it's compressed state and becomes quite cold, just as freon does in a heat pump. The heat had already been transfered to the outer layers, which when exiting the tube are very hot.




This is all very nice, but how can we use this? Well, by pulsing a vortex we can do some interesting things. I designed a vortex generator for my motorcycle which automatically gets pulsed. As the air is drawn into the cylinder, it first goes through a device which develops a strong vortex. This fast spinning column of air is fed directly through the throttle body and into the cylinder. This, in and of itself, would only serve to mix the fuel and air a little better if it weren't for and interesting thing that happens between cycles. When the intake valve closes, the air stops its linear movement, but the vortex continues to rotate. This rotation, as we saw above, continues to compress the air in the core. It also continues to draw air into the vortex by virtue of its low pressure. It becomes a turbo charger.
When the intake valve opens again, what does it get? It gets compressed air. Engines run much better on compressed air, as my bike and car have both shown. The air also has far less friction traveling through the intake tube and throttle body due to the layering of the air. This creates virtually friction free travel for the air column (no turbulence created on internal surfaces).
What I am planning to do now with this principal is to use it in a water turbine, similar to the home power unit Victor Schauberger build back in the '50s. I'll use centrifugal force to provide the pressure, and a pulsed vortex to convert it to rotational power. I've been working on this concept off and on for over a year now, but only recently solved some rather difficult mechanical issues. I'll be starting from scratch again and plan to build this device in half of a 55 gallon drum. I'll be using concepts learned from building a number of mechanical engines, as well as a few earlier turbine attampts. And, with a little help from Mr. Bernoulli and others, we'll see what happens.

Cheers,

Ted